Outdoor advertising is growing in importance as commuters spend more time on highways. The rear of cargo trailers and delivery vehicles present a challenge for wide carriage graphics because the doors must remain free to open and close in the normal conduct of business. The rear face of the cargo trailer is the location of the cargo doors. Cargo doors typically are of two types: swing-open doors and overhead doors. An exemplary swing-open door system 100 is illustrated in FIG. 1A. Swing-open door systems 100 include a door frame 110 and an opening that provides access to the cargo area. A pair of doors 120 is positioned within the opening. The doors 120 are each hinged on one vertical side (the exterior side) such that the doors open outward. The doors 120 possess roughly the same dimensions and are configured such that, when swung closed, they meet in a vertical seam along in the middle of the opening. Swing door systems may also include vertically-running locking bars 125 on the outer face of one or both of the swing doors.
FIG. 1B illustrates a typical overhead or roll-up door system 130. As illustrated, an overhead or roll-up door system 130 includes has a door frame 140 with and opening that provides access to the cargo area. A door 150 is positioned within the opening. The door 150 is formed from a series of panels 160 that are hinged together such that they “break” as they slide along a track built into the top of the cargo space. A typical overhead door is formed from multiple panels (18 to 24 inches high) that run the full width of the cargo door area. These panels are joined along the horizontal edges so that they form a semi-flexible belt that can slide up and around the bend radius of the track built into the top of the cargo compartment. Handles for lifting and closing the roll up door, and any appropriate locking hardware, is typically fastened in the middle of the bottom panel.
Attaching a seamless, large-area advertising image to either of these rear door systems is problematic. In the case of the swing door systems 100, the image will have to be fabricated and installed in at least two parts (one for each door) and, frequently, will be obscured and further striated by the vertical locking bars noted above which stand off several inches from the plane of the doors themselves. In the case of the roll up door systems 130, the advertising image must be fabricated in small segments and individually installed on each of the horizontal panels 160. Even when this installation process is precisely done, the flexible seams between each horizontal panel (necessary so that the roll up door system can function) leave noticeable seams through the advertising message.
The less-than-desirable end product, along with the inherent difficulty of installing these advertising messages properly, has limited the exploitation of the advertising potential of the rear doors on these cargo vehicles. Consequently, the wide carriage, full-color graphic images so prized by the outdoor advertising industry are virtually absent from this prime space.
Attempts have been made to address the above drawbacks. For example, one attempt stretches a semi-elastic polymer or fabric with indicia over several or all of the horizontal panels 160 in a roll-up door 150. This approach, however, does not work for swing door systems, necessitating two very different solutions for the most common door systems in use. This means that a truck fleet owner/operator managing a diverse population of vehicles has to limit any advertising campaign to only those fitted with roll-up door systems, or would have to find a second solution and then maintain two parallel advertising systems with differing spare and repair parts inventories and different graphic production and design approaches.
Additionally, the stretched fabric or polymer approach requires that the sheet materials with indicia on the outer surface be able to accommodate the repeated expansion and contraction of the seams between the break panels without any fraying, paint/ink peeling or discoloration, or creasing/sagging if the flexible substrate cannot restore to the exact dimensions prior to the stretching. The requirement for the sheet materials with indicia on the outer surface to constantly flex, stretch, and restore also makes any backlighting scheme impractical. Backlighting options such as electroluminescent (EL) panels are inelastic; consequently, an EL panel used for backlighting would not be able to stretch in proper overlay alignment with the outer sheet materials, potentially causing the backlighting to come loose and degrade the overall presentation.
Another approach utilizes two panels that are mounted to the left and right swinging doors, with the panels opening and closing with the doors. When closed, the two advertising panels would come together to form a display across the width of the doors. Spacers would hold the two advertising panels at the appropriate standoff distance from the doors themselves to accommodate and hide the vertical locking bars. This approach is suffers from significant drawbacks, since it addresses only the swing door installation and not the roll up door installations. There is no swinging door in the roll up door configuration; consequently, there is no place to attach the two advertising panels. This would again necessitate the fleet manager to maintain two separate advertising systems in order to run a fleet-wide advertising campaign.
Additionally, in order for the advertising panels to come together in a ‘seamless’ presentation, there can be no misalignment even after repeated heavy use. The same geometry that would provide a ‘seamless’ merge of the two advertising panels under ideal conditions will cause a noticeable vertical seam to appear at or close to the middle of the advertising display, degrading the presentation. Furthermore, merging two backlighting systems perfectly to form a “seamless” backlit display will be problematic given the requirement to safely insulate the edges of any illumination scheme, EL panel or otherwise. Even a slight spacing between the two backlit panels will create a detectable dark line down the middle of the display.
Thus, it would be desirable to provide a signage system operable for use on roll-up and swinging door systems that provides a seamless display and fully supports both day and night (backlit) presentations.